The good news
I believe I’m close to publishing a NixOS package for sc3-plugins.
The problem
Long ago I inistalled SuperCollider (3.11.2) via the NixOS packaging system. And today I think I managed to build sc3-plugins too, by writing a Nix expression for it. But I can’t seem to get SuperCollider to recognize the extensions.
Details
I know scide is working, because I can produce sound from ordinary builtin UGens. But if I try to evaluate, say, this example from the Decimator documentation:
{Decimator.ar(SinOsc.ar([400, 404], 0, 0.2), MouseX.kr(0, 44100), MouseY.kr(0, 31))}.play
I get this error:
-> Synth('temp__3' : 1003)
exception in GraphDef_Recv: UGen 'Decimator' not installed.
*** ERROR: SynthDef temp__3 not found
FAILURE IN SERVER /s_new SynthDef not found
According to Platform.userExtensionDir, my local Extensions folder is /home/jeff/.local/share/SuperCollider/Extensions.
When, in the sc3-plugins folder that Nix built, I search for a folder called SC3plugins, the only result is /nix/store/591z795zn2na6q0976b3ix0lk5nywgkv-sc3-plugins-3.11.1/share/SuperCollider/Extensions/SC3plugins. And it certainly looks like a folder full of extensions:
jeff@jbb-dell:SC3plugins$ pwd
/nix/store/591z795zn2na6q0976b3ix0lk5nywgkv-sc3-plugins-3.11.1/share/SuperCollider/Extensions/SC3plugins
jeff@jbb-dell:SC3plugins$ ls
AntiAliasingOscillators ConcatUGens MdaUGens SkUGens
ATK DEINDUGens MembraneUGens SLUGens
AuditoryModeling DistortionUGens NCAnalysisUGens StkInst
AYUGens DWGUGens Neuromodules StkUGens
BatUGens GlitchUGens NHUGens SummerUGens
BBCut2UGens HOAUGens OteyPianoUGens TagSystemUGens
BerlachUGens JoshUGens PitchDetection TJUGens
BetablockerUGens LadspaUGen QuantityUGens VBAPUGens
BhobUGens local RFWUGens VOSIMUGens
BlackrainUGens LoopBufUGens RMEQSuiteUGens
ChaosUGens MCLDUGens SCMIRUGens
jeff@jbb-dell:SC3plugins$ tree MdaUGens/
MdaUGens/
├── HelpSource
│ └── Classes
│ └── MdaPiano.schelp
├── MdaUGens.html
└── MdaUGens.sc
2 directories, 3 files
So I made a symlink from my local user extensions folder to that SC3plugins folder:
jeff@jbb-dell:Extensions$ ln -s /nix/store/591z795zn2na6q0976b3ix0lk5nywgkv-sc3-plugins-3.11.1/share/SuperCollider/Extensions/SC3plugins SC3plugins
jeff@jbb-dell:Extensions$ pwd
/home/jeff/.local/share/SuperCollider/Extensions
I know SC is actually paying attention to that user extensions folder, because when I made a symlink to the wrong thing, the server would crash as soon as I booted it, whereas the symlink above allows the server to start normally.